Speed-equalizing device for phonographs, &amp;c.



C. H. GREEN.

SPEED EQUALIZING DEVICE FOR PHONOGRAPHS, m.

APP] ICATION HLED JUNE I4. 19I8.

Patented Aug'. 16, 1921.

2 $HEETSSHEET I.

C. H. GREEN.

SPEED EQUALiZIT'JG DEVICE FOR PHONOGRAPHS, &c.

APPLICATION FILED JUNE 14, I918.

2 9 L m 1 n y m m i M o d 0 2 e r n W 1 e t no H L m 5 unirao STAT-ES PATENT orrice.

CLIFFORD H. G'BEIHQ 0F GRAND RAPIDS. MICHIGAN. ASSIGNOR T0 NATIONAL PIANO MANUFACTURING COMPANY, OF GRAND RAPIDS, MICHIGAN, A. CORPORATION 013 I L-mots.

s'rnnnnouamzmo DEVICE FOR rnonooaarns sc.

Application filed June 14.,

lie it known that laclm-rono H. (iRI-ZI'IN,

a citizen of the l nited States. residing at.

(lrand Rapids. in the county of Kent and State of'Michigan, have invented new and useful improvements in peed-Equalizing Devices for lhonographs. &c.. of which the following is a full, clear. and exact description.

.vly invention relates to actuating mechanism for revolving meclninical devices, and particularly the actnating mechanism for the records of 'phonographs and graphophones.

The electric motors now in extensive use forwinding the springs in the mechanism for revolving the records of phonographs 'must be started whenever the spring needs .windi'ng and stopped whenever the spring is suilieiently rewound. 'lhese motors are affected by the variations in the voltage of the electric current used to operate them. The greaterthe voltage the greater the speed. I-he pitch of the sound reproduced "from the records in the phonograph varies 'with the speed. so it will be apparent that in order to obtain an-. bsolutely correct reproduction of sound. the ctfeet resulting, primarily. from the variations of the voltage must be overcome;

The objects of my invention are to render the starting and stopping of the electricmotor imnecessary, in view of the fact that the motor can run all the-time.':md to maini be! at I will not beafi'ected by the variations of the suits by the means hereinafter tain the rotation of the record bearing mema given predetermined speed which 1 aecom dish-these i*e-= fully departicularly pointed out 1n speed of the motor.

scribed,- and as the claims. I

In the drawings: 1

v Figure l is a side vierof a motor driven actuating mechanism for the records of phonographs attached to the underside of a fragment of the record supporting platform showing myimprovements applied thereto.

Fig. 2. is a horizontal view thereof taken on dottedline 2+2. Pi 1, looking in the direction indicated by 't e arrows. i

Figs. 3, d and 5 are detail views illustratiugthe construction of the device for transmitting the motion derived from the elec- Specification of Letters Patent.

' the medium of which Patented Aug. 16,1921.

1918. Serial Ho. 239,981.

-npper end of a vertical shaft C joulnaled ill the center of said platform and 6 the metal frame work which is secured to and depends from the underside of the platform in which the actuating mechanism for the turntable is assembled.

Shaft (1 extends down through the top plate of frame work (5 and has the heel thereof journaled in suitable hearings in the lower plate of said frame work. Just above its lower bearings shaft C has a. comparatively large gear 7 securely mounted thereon which meshes with a barrel-pinion 8 on the lower end of a vertical shaft 9 which latter is. preferably, likewise journaled in the top and bottom plates of frame work 6. Near its upper end this last mentioned shaft S) has a wo rm-gear 10 securely mounted thereon which meshes with and drives a worm 12 on a horizontal shaft 13 that is journaled in upright members arising from the bottom plate of said framework 6. Between its bearings shaft 13, is provided with any suitable kind of a centrifugal governor llasubstantially as shown in the drawings, and this governor includes a disk 26 securely mounted on one end of shaft 13 which is engaged by a brake (not shown). The centrifugal governor and the brake mechanism, just mentioned, while necessary. do not form any part of my invention, and it is, therefore, deemed unnecessary to describe the same in detail.

About midway between gear 7 and the upper plate of ramework 6 shaft C has a large gear 16 loosely mounted thereon and held in place by a collar 16 securely fastened to said shaft, and this gear is engaged by a worm 17 mounted upon a horizontal shaft 27. that is journaled in suitable standards made'integral with framework 6. One end of shaft 27 extends through its bearlugs and has a sheave l8 thereon through and a belt 19 said shaft 27 is driven by an electric motor X. Motor X is constructed in accordance with any of the small electric motors now on the market, and is fastened to and suspended from the underside of platform A, and instead of driving shaft 27 through the me dium of-a belt and sheave it may be geared to said shaft, or, for that matter, said shaft 27 may be extended and constituted the armature shaft of a motor.

Gear 16 is connected to and. supports a circular casing 20 above it by means of corresponding spacing bolts 21', 21, and this casing is concentric to and looseon shaft C. The upper portion of casing is more or less of an inverted cup-shape, except that its circular edges are flanged outward, and the mouth thereof closed by means of a circular plate 22, the margins of which are secured to the annular edges of the casing by means of screws or bolts. The inner circumference of the cylindrical side of the casing has an annular leather. facing tightly fitted therein and secured thereto by cement or other suitable means. Inclosed within this leather facing is a spiral expansion spring 2% which is made of flat steel and has its incertain speed. When the casing revolves at.

a greater speed than said predetermined speed. greater friction will be generated between its inner circumference and the outer convolution of the spring, and said outer convolution will wind slightly aini thus contract the diameteroi the perimeter of the spring. The 'casi will. hen slio and move faster than the \ring and cease to impart motion to the sea and shaft (3 during mo nientary short intervals, thus, catching hold of and imparting a forward motion to and then releasing the spring-but: not to the extent of winding the spring so that it can of itself and una ded by said continuously revolving motor drivesha'ft C, but only to the extent of imparting sufficient portion of the motion to the casing to said shai't C- to cause the latter to revolve at the predetermined speed-it is desired to impart to the record bearing member. a

In operation, electric motor X imparts motion to shaft 27, which, throiw'h the medium of worm 17 revolves gear in. as here-- inbefore stated, gear 16 is connected to and imparts its motion to the casing, and the.

latter through the medium of the leather facing in its interior imparts a motion to and WlIlClS up spring 24 by reason of the frictional engagement between the same and teem- 04 the outer convolution of the spring until said spring has been wound up and the daur etcr of the'outer convolution thereof is decreased in diameter to such an ex it that its 'i'rictional contact with the said facing will no longer be suiiicient to wind the spring, whereupon the convolution or the casing will no longer impart its motion to thespring. The lat-ten therefore, when at its certain minimum tension, will. receive motion from the casing and when at a certa n maximum tension 1t will-cease to talus motion therefrom. It will thus be evident that the motor may run all the time and. that the spring as it automatically unwinds will impart motion to shaft' C at a certain non ma: speed that will not vary, thus insuring the rotation of shaft (.l, the turntable mount" ed thereon and the record mounted upon said shaft at a reliable and equablc speed, which will not vary the pitch of sound rcproduced by the record and will result in a correct reproduction of" the instrumental or vocal matter of the record.

It is possible to use my improvements without the use of the governor, but 1 pre .icr to use ,it in connection therewith, because it regulates the speed and the governor preventsany variation in that speed. as for, instance, at the moment when the spring to be wound by the leather facing and when said spring; again commences to re ccive motion therefrom.

' hat l claim as new is i. In speed equalizing devices for phonouraphs, the combination with a revolublc lrivenmember, and a revoluble driving member, of a contrivance consisting of two parts the peripheries of which are frictionally engageable, one of which is permanently connected to the driven member and the other to the driving member, to the former oi which motion is imparted through the medium of said tarts, while the driving member is revolving below a predetermined speed. 2. .ln speed equalizing devices for phonographs, the .mzubination with a revoluhle driven memocxi" and a revolublc driving ,member, of a contrivance consisting of two concentrically arranged parts, the berinh cries of which are irictionally ei'igaggeable, one of which is permanently connected to thedrivcn member and the other to the driving member, to the. former of which motion is imparted through the medium. of said parts, while the driving member is revolving' below a predetermined speed.

3. in speed equalizing devices for phonographs, the combination with a revoluble driven member and a rcvoluble. driving member, of a contrivance consisting" oi two parts, one of which is expansible and permanently connected to the driven member and the other of which surrounds said pansible part and is connected to said driving member and imparts motion to the driven member only at a predetermined 4. In speed equalizing devices for phonographs, the combination with a revoluble turntable, a shaft on the upper end of which said turntable is mornted. and a spiral spring the inner end of which is perma nently secured to said shaft, of an annular member surrounding said spring concentric to said shaft and adapted to frictionally engage the outer convolution of said spring,-

and mechanism for revolving said annular member.

In speed equalizing devices for phonographs, the combination. with a revoluble turntable, a shaft on the upper end of which said turntable is mounted, and a spiral spring the inner end of which ispermanently secured to said shaft, a, casing surrounding said spring concentric to said shaft and having an inner annular surface and adapted to be frictionally engaged by the outer-ccmvolution of said spring, and mechanism for revolving said' annular member.

6. In speed equal-izing'devices for phonographs, the combination with a .revolilble' t urntable,'a shaft on the upper end of which said turntable. is mounted, and a spiral spring the inner end of which is permanently secured to said shaft, of an annular casing surrounding said spring concentric to said shaft, an annulus in the interior of said casing adapted to be frictionally engaged by the outer convolution of said spring, and mechanism for revolving said annular member;

7. In speed equalizing devices for phonographs, the combination with a revoluble turntable, ashaft on the upper end of which said turntable is mounted, and a spiral spring the inner end of which is permasurface and nently secured to said shaft. of an' annular casing surrounding said spring concentric to said shaft, and havingan inner annular adapted to be frictionally engaged by the outer convolution of said spring, a gear connected to said casing, a motor, and gearing from vsaid motor to said-first mentioned gear. v

8. In speed equalizing devices for phonographs, the combination with a revoluble turntable, a shaft on the upper end of which said turntable is mounted, and a spiral spring the inner end nently secured to said shaft, member surrounding said spring concentric to said shaft and adapted to eugagetbe outer convolution of said spring, mechanism for revolving gear securely mounted on said shaft, and governor mechanism driven thereby.

9. In speed equalizing devices for phonographs, the combination with a re'voluble turntable, a shaft on the upper endof which s'aidturntable is mounted, and a spiral spring the inner end of' which is permanently scoured to said shaft, of an annular casing surrounding said shaft and having adapted to be frictionally engaged by the outer convolution of said spring, a gear connected to said casing, a motor and gearing for transmitting motion from said motor to said first mentioned gear, a gear securely mounted on said shaft, and governor mechanism driven thereby.

In witnesswhereof I have hereunto set my hand this 23rd day of April, 1918.

CLIFFORD H. GREEN.

of an annular Witnesses A= Lawnnnos ANnnnsoN, W. Ivon.

transmitting mot-ion of which is perma-- said annular member. a

spring concentric to said ail-inner annular surface 

